Abstract: Carboxymethylcellulose(CMC) hydrogels have attracted attention as biodegradation absorbent materials in agriculture and forestry. It is important to investigate the biodegradation behavior and kinetics of the bio-degradable reaction. In this paper, CMC hydrogel was prepared by crosslinking with aluminum chloride. The effects of the substrate concentration, enzyme concentration and reaction temperature on the degradation rates were investigated. At the same time, the kinetics of the enzymatic degradation and the relationship between the apparent-activation energy and enzyme concentration were also discussed in detail. The results showed that the optimal temperature for the enzymatic reaction was 37 ℃.The reaction orders for the substrate and enzyme were 1 and 1.2, respectively. A new kinetic model for CMC hydrogel heterogeneous degradation was proposed which was different from the traditional Michaelis-Menten kinetics. The relationship between the apparent-activation energy and the enzyme concentration was also established.

Key words: Carboxymethylcellulose(CMC), Hydrogel, Bio-degradation, Kinetics